Abstract: A jet break-off length measurement apparatus for a continuous liquid drop emission system is provided. The jet break-off length measurement apparatus comprises a liquid drop emitter containing a positively pressurized liquid in flow communication with at least one nozzle for emitting a continuous stream of liquid. Heater resistor apparatus is adapted to transfer pulses of thermal energy to the liquid in flow communication with the at least one nozzle sufficient to cause the break-off of the at least one continuous stream of liquid into a stream of drops of predetermined volumes. A sensing apparatus adapted to detect the stream of drops of predetermined volumes is provided. A control apparatus is adapted to determine a characteristic of the stream of drops of predetermined volumes that is related to the break-off length. Further apparatus is adapted to inductively charge at least one drop and to cause electric field deflection of charged drops.

Abstract: A continuous ink jet printing system capable of printing at multiple predetermined print resolutions. The system comprises a drop generator having an array of nozzles for emitting a plurality of continuous streams of liquid for applying ink to media driven in a media advance direction having a source for pressurized liquid for supplying pressurized liquid to the plurality of nozzles. The plurality of nozzles have effective nozzle diameters D0 and a stimulation device associated with each nozzle of the plurality of nozzles for forming ink drops having predetermined drop volumes from the continuous streams of liquid. The predetermined drop volumes include non-print drops of a unit volume V0, and print drops having volumes that are integer multiples of the unit volume, mV0, wherein m is an integer greater than 1. A catcher collects the non-print drops and a selector selects a predetermined print resolution. Each predetermined print resolution has a corresponding print drop volume mV0.

Abstract: The generator according to the invention operates by strong stimulation in the form of pulses (?) so as to generate drops, particularly for ink jet printing purposes. This choice enables breaking the jet (30) close to the ejection (16) and reduces the interference ratio. A generator with piezoelectric stimulation is particularly suitable.

Abstract: An inkjet recording apparatus includes a nozzle, a charging electrode, a deflecting electrode, a storage device, and an authentication device. The nozzle atomizes a supplied ink into ink particles by exciting and ejecting the supplied ink. The charging electrode electrically charges the ink particles. The deflecting electrode forms an electric field that deflects the ink particles electrically charged. The storage device storing therein a program(s) that implements a predetermined printing function(s). The predetermined printing function(s) becomes executable upon connection of an authentication key to the authentication device.

Abstract: A charge plate and a method for fabricating a charge plate for an ink jet printhead includes the steps of removing portions of conductive material from a dimensionally stable substrate with a coating of conductive material to form at least a first and second electrode on a first face with a first space between the first and second electrodes, removing portions of conductive material from the dimensionally stable substrate with a coating of conductive material to form a first electrode extension which engages the first electrode on the conductive charging face, and a second electrode extension which engages the second electrode on the conductive charging face, whereby the first and second electrode extensions are electrically isolated from each other, additionally forming a first space between the electrode extensions, which connects with the first space between the electrode extensions.

Abstract: A method includes forming drops of first size by applying drop-forming pulses during unit time period, ?0; forming drops of second size by applying drop-forming pulses during second size drop time period, ?m, wherein the second sized drop time period is a multiple, m, of the unit time period, ?m=m*?0, and m?2; providing timing between drops for printing consecutive pixels is equal to ?i=a*?0 where a is an integer ?m and is a function of print media speed; forming the corresponding plurality of drop forming pulse sequences so as to form non-print drops and print drops according to the liquid pattern data; delaying the timing of the drop forming pulses sent to the transducers of the second group relative to the drop forming pulses sent to the transducers of the first group by a delay time ?L which is approximately equal to ?i/2.

Abstract: The invention concerns inkjet printers with binary continuous jet, the printing principle of which is based on the differential deflection of jets or jet segments. According to the invention, by virtue of a judicious selection of pulse periods of the electrical generator, the print speed of such printers is optimised while guaranteeing precision of the two deflection levels (binary).

Abstract: A method and droplet selection device are provided for a continuous printer for selectively ejecting a second droplet and to have it collided with a predefined first droplet. In particular, the device comprises a first droplet ejection system arranged to generate a continuous stream of first droplets from a fluid jetted out of an outlet channel; and a second droplet ejection system arranged to generate second droplets for colliding the second droplets into the first droplets so as to selectively deflect the first droplets from a predefined printing trajectory. The second droplet ejection system comprises a control circuit to selectively eject the second droplet and to have it collided with a predefined first droplet.

Abstract: A printer includes a printhead and a source of liquid. The printhead includes a nozzle bore. The liquid is under pressure sufficient to eject a column of the liquid through the nozzle bore. The liquid has a temperature. A thermal modulator is associated with the nozzle bore. The thermal modulator is operable to transiently lower the temperature of the liquid as the liquid is ejected through the nozzle bore. An electrical pulse source is in electrical communication with the thermal modulator. The electrical pulse source is operable to provide a series of pulses to the thermal modulator that control the transient temperature lowering of the liquid. The series of pulses includes a first pulse applied at a first power level for transferring heat to the liquid, a second pulse applied at a second power level for transferring heat to the liquid, and a third pulse applied at a third power level for transferring heat to the liquid. The third power level is in between the first power level and the second power level.

Abstract: An ink jet device including a plurality of ink channels that are arranged side by side and are covered by a flexible sheet, and a corresponding number of actuators are arranged to exert an actuating force onto the sheet through a bump that has a trapezoidal cross-sectional configuration wherein the bumps are formed on the sheet in such an orientation that their trapezoidal cross-section diverges towards the actuator, and the bumps are bonded to the actuators by means of an adhesive.

Abstract: The apparatus and method use an optical feedback system to align a transducer with a stent strut. Once alignment is achieved, the transducer causes a coating to be ejected onto the stent strut and the transducer is moved along the stent strut to coat the stent strut.

Abstract: A method includes forming drops of first size by applying drop-forming pulses during unit time period, ?0; forming drops of second size by applying drop-forming pulses during second size drop time period, ?m, wherein the second sized drop time period is a multiple, m, of the unit time period, ?m=m*?0, and m?2; providing timing between drops for printing consecutive pixels is equal to ?i=a*?0 where a is an integer?m and is a function of print media speed; forming the corresponding plurality of drop forming pulse sequences so as to form non-print drops and print drops according to the liquid pattern data; delaying the timing of the drop forming pulses sent to the transducers of the second group relative to the drop forming pulses sent to the transducers of the first group by a delay time ?L which is approximately equal to ?i/2.

Abstract: In an ink-jet printing a succession of ink droplets are projected along a longitudinal trajectory at a target substrate. A group of droplets is selected from the succession in the trajectory, and this the group of droplets is combined by electrostatically accelerating upstream droplets of the group and/or decelerating downstream droplets of the group into a single drop.

Abstract: A method for creating composite droplets for use in an ink jet system includes a first fluid (1) brought into contact with a second fluid within a set of channels (5,14). The interface between the fluids is characterised by an interfacial tension. The first fluid forms spaced droplets (8) within the second fluid, the composite of the first and second fluids passing through an orifice (6) to form a jet (9).

Abstract: A continuous drop emitter includes a liquid supply chamber containing a liquid held at a positive pressure. First and second nozzles are in fluid communication with the liquid supply chamber and emit first and second continuous streams of a liquid. First and second stream break-up transducers independently synchronize the break up of the first and second continuous streams of the liquid into first and second streams of drops. An acoustic damping material is located adjacent to or within the liquid supply chamber for damping sound waves generated within the liquid chamber by the first and second stream break-up transducer. The continuous drop emitter can be configured with a Helmholtz resonant chamber tuned to a critical stimulation frequency having an acoustic damping material located therein.

Abstract: A continuous multi-nozzle inkjet recording apparatus includes a multi-nozzle inkjet head including a liquid chamber, an ink nozzle plate, and a heating unit, a gas flow applicator, a cap, and a gutter unit. The ink nozzle plate includes ink jetting nozzles to jet ink column. The heating unit stimulates the pressurized ink at an exit opening of the ink jetting nozzles to separate ink droplets from the ink column. The gas flow applicator applies a gas flow to flying ink droplets. The gas flow applicator includes an opening to jet the gas flow. The cap shields an area of the gas flow from an ambient atmosphere space existing around a transporting and image forming area for the recording medium. The gutter unit catches ink droplets. Ink droplets not caught by the gutter unit are directed onto a recording medium to form an image on the recording medium.

Abstract: A droplet generating device for use as part of a continuous inkjet printer comprises a set of channels for FLUID providing a composite flow of a first fluid (11) surrounded by a second fluid (12) and an expansion cavity (3) having an entry orifice (2) and an exit orifice (4). The cross sectional area of the cavity is larger than the cross sectional area of either orifice such that the composite flow breaks up to form droplets of the first fluid within the second-fluid within the cavity, the exit orifice also forming a nozzle of an inkjet device, the passage of the droplets of the first fluid through the exit orifice causing the composite jet to break into composite droplets.

Abstract: A method is disclosed for forming a liquid pattern including forming non-print drops by applying non-print drop forming energy pulses during a unit time period, ?0, and forming print drops by applying print drop forming energy pulses during a large drop time period, ?m, wherein the large drop time period is a multiple, m, of the unit time period, ?m=m?0, and m?2; and a corresponding plurality of drop forming energy pulses sequences are formed so as to form non-print drops and print drops according to the liquid pattern data. The corresponding drop forming energy pulse sequences applied to adjacent drop forming transducers are substantially shifted in time so that the print drops formed in adjacent streams of drops are not aligned along the nozzle array direction.

Abstract: A method and apparatus for forming fluid droplets includes a nozzle channel, a pressurized source of a non-conductive fluid in fluid communication with the nozzle channel, and a stimulation electrode. The pressurized source is operable to form a jet of the non-conductive fluid through the nozzle channel. At least one portion of the stimulation electrode is electrically conductive and contactable with a portion of the non-conductive fluid jet. The at least one electrically conductive and contactable portion of the stimulation electrode is operable to transfer an electrical charge to a region of the portion of the non-conductive fluid jet with the electrical charge stimulating the non-conductive fluid jet to form a non-conductive fluid droplet.

Abstract: A continuous inkjet system and method has a stimulation device producing a modulation in a liquid jet having a wavelength ? and causing a first liquid droplet to break off from the liquid jet and travel along a path and causing a second liquid droplet to break off from the liquid jet and travel along the path. The first liquid droplet has a first break off length and the second liquid droplet has a second break off length longer than the first break off length. The first break off length and the second break off length have a difference of at least one wavelength ? in response to stimulation pulses.

Abstract: A liquid droplet deposition method of consecutively depositing a plurality of droplets of liquid, which contains solvent and particles dispersed in the solvent and having a substantially uniform size, onto a recording medium includes the steps of: determining target positions at which the plurality of droplets are to be deposited on the recording medium; depositing an X-th droplet of the droplets at an X-th target position of the determined target positions on the recording medium, X being a natural number; and depositing an (X+1)-th droplet of the droplets at an (X+1)-th target position of the determined target positions on the recording medium subsequently to the X-th droplet, after the particles contained in the X-th droplet are aggregated to form an X-th particle aggregate on the recording medium due to liquid bridging force, wherein in the determining step, the target positions are determined so as to satisfy following conditions: L(CX, CX+1)?rX+r_maxX+1, and L(PX, CX+1)?r_maxX+1, where CX is the X-th

Abstract: A highly viscous fluid discharging apparatus includes: a nozzle including a discharge opening having a predetermined inner volume, and a widened portion formed at a position immediately before the discharge opening and expanding from the discharge opening; a plunger capable of opening and closing the discharge opening by causing the leading-end portion of the plunger to move away from and to move towards the widened portion; and a driver configured to move the plunger in a direction of closing the discharge opening against a biasing force that biases the plunger in a direction of opening the discharge opening. During a stand-by period, the discharge opening is kept closed by an action of the plunger that is caused by the driver to press the leading-end portion onto the widened portion.

Abstract: A method and apparatus for inkjet printing by means of a plurality of inkjet nozzles arranged in at least one row and having spaced, parallel nozzle axes for emitting liquid ink drops towards the substrate, and multi-level charging and deflecting plates controlled to deflect individual drops to selected locations on the substrate with respect to the respective nozzle axis according to the pattern to be printed. The multi-level charging and deflecting plates are controlled to cover, for each nozzle, a line section which includes two non-contiguous deposit zones to receive ink drops from the respective nozzle, separated by a non-deposit zone not to receive ink drops from the respective nozzle.

Abstract: A method is disclosed for forming a liquid pattern of print drops impinging a receiving medium according to liquid pattern data using a liquid drop emitter that emits a plurality of continuous streams of liquid at a stream velocity, vd, from a plurality of nozzles having effective diameters, Dn, arrayed at a nozzle spacing, Sn, along a nozzle array direction that are broken into a plurality of streams of print and non-print drops by a corresponding plurality of drop forming transducers to which a corresponding plurality of drop forming energy pulse sequences are applied.

Abstract: A jet break-off length control apparatus for a continuous liquid drop emission system is provided. The jet break-off length control apparatus comprises a liquid drop emitter containing a positively pressurized liquid in flow communication with at least one nozzle for emitting a continuous stream of liquid. Resistive heater apparatus is adapted to transfer pulses of thermal energy to the liquid in flow communication with the at least one nozzle sufficient to cause the break-off of the at least one continuous stream of liquid into a stream of drops of predetermined volumes. A sensing apparatus adapted to detect the stream of drops of predetermined volumes is provided.

Abstract: A continuous liquid drop emission apparatus is provided. The liquid drop emission apparatus is comprised of a liquid chamber containing a positively pressurized liquid in flow communication with at least one nozzle for emitting a continuous stream of liquid and a jet stimulation apparatus adapted to transfer pulses of energy to the liquid in flow communication with the at least one nozzle sufficient to cause the break-off of the at least one continuous stream of liquid into a stream of drops of predetermined volumes. The continuous liquid drop emission apparatus further comprises a semiconductor substrate including integrated circuitry formed therein for performing and controlling a plurality of actions on the drops of predetermined volumes. The plurality of actions may include drop charging, drop sensing, drop deflection and drop capturing. Drop action apparatus adapted to perform these functions and integrated circuitry to control the drop action apparatus are formed in the semiconductor substrate.

Abstract: A continuous liquid drop emission apparatus is provided. The liquid drop emission apparatus is comprised of a liquid chamber containing a positively pressurized liquid in flow communication with at least one nozzle for emitting a continuous stream of liquid and a jet stimulation apparatus adapted to transfer pulses of energy to the liquid in flow communication with the at least one nozzle sufficient to cause the break-off of the at least one continuous stream of liquid into a stream of drops of predetermined volumes. The continuous liquid drop emission apparatus further comprises a semiconductor substrate including integrated circuitry formed therein for performing and controlling a plurality of actions on the drops of predetermined volumes. The plurality of actions may include drop charging, drop sensing, drop deflection and drop capturing. Drop action apparatus adapted to perform these functions and integrated circuitry to control the drop action apparatus are formed in the semiconductor substrate.

Abstract: A printhead has a fluid chamber having an orifice, an associated fluid drop forming mechanism, and an associated fluid drop steering device. The fluid drop forming mechanism is operable to apply to fluid present in the fluid chamber energy sufficient to cause a fluid drop to be ejected from the orifice. The fluid drop steering device is operable to optionally apply to fluid present in the fluid chamber energy insufficient to cause drop formation prior to the fluid being ejected from the orifice. The fluid drop steering device is distinct from the fluid drop forming mechanism.

Abstract: A continuous drop emitter comprising a liquid supply chamber containing a liquid held at a positive pressure; first and second nozzles in fluid communication with the liquid supply chamber nozzles emitting first and second continuous streams of a liquid; first and second stream break-up transducers adapted to independently synchronize the break up of the first and second continuous streams of the liquid into first and second streams of drops of predetermined volumes, respectively; and an acoustic damping material located adjacent to or within the liquid supply chamber for damping sound waves generated within the liquid chamber by the first and second stream break-up transducer. The continuous drop emitter may also configured with a Helmholtz resonant chamber tuned to a critical stimulation frequency having an acoustic damping material therein for absorbing acoustic stimulation energy.

Abstract: Methods are provided for analyzing characteristics of fluids in the context of an acoustic ejection system. Such a system has a controller, an acoustic radiation generator, and a coupling medium coupling the radiation to a reservoir holding fluid. The methods can use acoustic radiation to both perturb a surface of the fluid in the reservoir and analyze the effect of the perturbation. The methods may use information about prior fluids. The methods of the invention can determine physical characteristics such as speed of sound and viscosity. The methods also include ways to determine a level of acoustic energy suitable to eject a droplet. Preferably the methods are executed automatically under control of programming of a controller of an acoustic ejection system.

Abstract: A method of driving a droplet jetting head comprising nozzle orifices to jet droplets, pressure generating chambers each of which can store liquid and communicate with one of the orifices, and pressurizing devices to change the pressures of the pressure generating chambers, comprising the steps of increasing the pressure in the pressure generating chamber by the pressurizing device and protruding liquid in the pressure generating chamber from the nozzle orifice as a droplet, and separating the liquid which protrudes from the nozzle orifice when ?/? is equal to or less than 1/3 where ?(?m) is the diameter (in micrometers) of an liquid pillar (protruded from the nozzle orifice) at the front end of the nozzle orifice and ?(?m) is the maximum diameter (in micrometers) of the liquid pillar.

Abstract: The liquid ejection head has: a surface acoustic wave propagation body in which a surface acoustic wave propagates; a nozzle orifice formed in the surface acoustic wave propagation body; a surface acoustic wave generation device which is provided on the surface acoustic wave propagation body around the nozzle orifice and excites the surface acoustic wave propagation body so that a surface acoustic wave is generated in the surface acoustic wave propagation body; a liquid supply device which supplies liquid to the nozzle orifice; and a guide member which is provided in a center of the nozzle orifice and has a tapered conical surface shape section that projects from an ejection surface of the nozzle orifice in an ejection direction, the liquid forming a curved liquid surface in the nozzle orifice in accordance with the tapered conical surface shape section due to surface tension, wherein the surface acoustic wave generates a capillary wave which propagates through the curved liquid surface in the nozzle orifice

Abstract: An inkjet printhead IC is fabricated using a wafer substrate that defines a plurality of ink inlet channels. A plurality of nozzle structures fabricated on the substrate to define nozzle chambers are in fluid communication with the ink inlet channels and an ink ejection nozzle in fluid communication with each nozzle chamber. Each nozzle structure has a chamber, an ejection nozzle in fluid communication with the chamber, and an ejection member for acting on ink within the chamber. A plurality of actuators attached to the substrate move each of the ejection members respectively, the movement being substantially parallel to the ink inlet flow direction; such that, ink is ejected through the ejection nozzle upon activation of the actuator corresponding to that nozzle structure.

Abstract: An image recording apparatus (2000) is disclosed, which comprises forming elements (2002) for forming an image, a memory (2006) indicating relative desirability of utilising the forming elements (2002) for forming the image, and processing means (2008) for computing image recording signals using input image signals (2012) and the stored data. The use of a particular forming element is thereby biased dependent upon the relative desirability data of other forming elements, the corresponding input signal for the particular forming element, and a term for the particular forming element.

Abstract: A system for delivering material onto a substrate. The system includes a jetting system having a reservoir containing the material and the reservoir includes a nozzle through which the material is expelled from the reservoir. An arcuate section is positioned between the reservoir and the nozzle. The material is configured to travel from the reservoir, through the arcuate section, and through the nozzle. The system also includes a means for applying pressure on the material contained in the reservoir, wherein the material is expelled from the reservoir through application of pressure by the means for applying pressure to thereby create a column of the material from the nozzle. A means for producing pressure modulations is located proximate the nozzle and is configured to substantially regulate formation of droplets from the column of the material. In addition, the system includes a charging ring configured to induce an electrical charge to selective ones of the droplets as they pass through the charging ring.

Abstract: A continuous stream binary array ink jet print head includes an elongate cavity for containing ink and an array of nozzle orifices formed so as to extend through a wall of the cavity for passing the ink from the cavity to form jets. The nozzle orifices extend along the length of the cavity. The cavity is divided up along its length by at least one internal wall thereby to create a plurality of sub-cavities substantially acoustically isolated from one another and to divide up the array of nozzle orifices between the sub-cavities such that each sub-cavity communicates with one or more of the nozzle orifices of the array. One or more actuators associated with each sub-cavity cyclically varies the dimensions of the sub-cavity thereby to cause the or each jet emanating from the nozzle orifice(s) of that sub-cavity to break up into ink droplets at a predetermined distance therefrom. The droplets of each jet are selectively electrically charged and deflected.

Abstract: A method, and apparatus for performing the method, are intended to prevent all of the ink discharged from a defective one of multiple nozzles in a continuous inkjet printhead from being used for printing on a print medium. This can be done by periodically heating the defective nozzle at a frequency that is greater than frequencies other nozzles which are not defective are periodically heated, to cause the defective nozzle to only discharge ink droplets that have a smaller volume than ink droplets discharged from the nozzles that are not defective. Then, the smaller volume droplets discharged from the defective nozzle are prevented from reaching a print medium, but the larger volume ink droplets discharged from the nozzles that are not defective are allowed to reach the print medium.

Abstract: There is provided an ink jet head for ejecting an ink liquid drop from an ink jet nozzle onto a recording medium, wherein, on a substrate having a heat conductivity of 15 (W/m/K) or less, a heat-transfer layer having a thickness of 10 ?m or more is formed, and a heat insulating layer is adjacently formed on top of the heat-transfer layer; and a heat generating heater, which has a thin film resistor for boiling a part of ink to generate a bubble and allow the ink liquid drop to be ejected from the ink jet nozzle by an expansion of the bubble and a thin film conductive electrode for supplying a current to the thin film resistor, is adjacently formed on top of the heat insulating layer. There is also provided an ink jet printer using the above ink jet head. The ink jet head and the ink jet printer as above make it possible to suppress the temperature elevation around the heat generating heater and yet enhance the printing speed upon the printing even if the ink liquid drop is continuously ejected.

Abstract: The invention provides devices and methods for acoustically assessing the contents of a plurality of reservoirs that are typically provided as an array. An acoustic radiation generator is employed for generating acoustic radiation having an image field of a size sufficient to interrogate a plurality of selected reservoirs at one time. The generator is placed in acoustic coupling relationship via a fluid acoustic coupling medium to the selected reservoirs, and acoustic radiation generated by the generator is transmitted through the coupling medium, an exterior surface of the selected reservoirs, and the selected reservoirs. A characteristic of the transmitted acoustic radiation is analyzed so as to assess the contents of each of the selected reservoirs. Fluid may be ejected from the selected reservoirs according to the assessment. Optionally, a means is provided for removing fluid acoustic coupling medium from the exterior surface after acoustic assessment.

Abstract: An apparatus for depositing droplets on a substrate is disclosed. The apparatus includes a support for the substrate, a droplet ejection assembly which includes a pumping chamber, a controller and a source of static pressure to maintain the total pressure in the pumping chamber above a threshold pressure level to avoid rectified diffusion type bubble growth in the pumping chamber. The droplet ejection assembly is positioned over the support for depositing the droplets on the substrate and includes, in addition to a pumping chamber, a displacement member and an orifice that ejects the droplets. The controller provides signals to the displacement member to eject drops.

Abstract: The invention provides devices and methods for acoustically assessing the contents of a plurality of reservoirs that are typically provided as an array. An acoustic radiation generator is employed for generating acoustic radiation having an image field of a size sufficient to interrogate a plurality of selected reservoirs at one time. The generator is placed in acoustic coupling relationship via a fluid acoustic coupling medium to the selected reservoirs, and acoustic radiation generated by the generator is transmitted through the coupling medium, an exterior surface of the selected reservoirs, and the selected reservoirs. A characteristic of the transmitted acoustic radiation is analyzed so as to assess the contents of each of the selected reservoirs. Fluid may be ejected from the selected reservoirs according to the assessment. Optionally, a means is provided for removing fluid acoustic coupling medium from the exterior surface after acoustic assessment.

Abstract: A system and method are provided for improving the reliability for operation of the eyelid associated with the ink jet printhead of a continuous ink jet printer. The eyelid actuation technique of the present invention solves the problem of ink jet fluid residue drying in or around the seal region between the eyelid and the catcher. This is accomplished by opening the eyelid at least once during the shutdown sequence of the printhead, while maintaining vacuum on the catcher throat. By opening the eyelid in this manner, the capillary forces that had held the ink jet fluid at the seal region are eliminated. The vacuum on the catcher throat then causes air to rush in through the gap between the catcher pan and the eyelid. Residual ink jet fluid at the seal region on both the eyelid and the catcher pan is then removed by the high velocity air moving through the gap.

Abstract: The present invention provides a method and device for the acoustic ejection of fluid droplets having a constant drop size from fluid-containing reservoirs having varying fluid heights contained therein without the need for repositioning the acoustic ejector in the z direction by adjusting the RF frequency and amplitude. In one embodiment, the device is comprised of: a plurality of reservoirs each adapted to contain a fluid; an ejector comprising a means for generating acoustic radiation, means for controlling the RF frequency and amplitude used to generate the acoustic radiation, means for focusing the acoustic radiation at a focal point near the fluid surface in each of the reservoirs; and a means for positioning the ejector in acoustically coupled relationship to each of the reservoirs. The invention is useful in a number of contexts, particularly in the preparation of biomolecular arrays.

Abstract: An eyelid positioning technique is provided for an ink jet printer to precisely position the eyelid relative to the catcher to properly seal the print head. The eyelid seals against the catcher to contain ink within the printhead on startup and shutdown of the printer system. An eyelid actuator assembly moves the eyelid into a sealed position for startup and shutdown and into an open position for print, so that ink jets can exit an array of orifices and pass between the catcher and the eyelid to print on a print media. At least one alignment flexure capability allows for precise positioning of the eyelid relative to the catcher or the drop generator during assembly of the printer system.

Abstract: A continuous color ink jet print head (40) for an electronic printing device is composed of a nozzle (42), pressurized ink sources (46, 48), and a print head surface (50) having channels (61, 62, 64, 66) disposed therein such that each channel (61, 62, 64, 66) is in communication with the nozzle (42). The continuous color ink jet print head (40) also includes a microvalve (52, 56) disposed within each of the channels (61, 62, 64, 66) such that each channel (61, 62, 64, 66) is connected through the microvalve (52, 56) to a pressurized ink source (46, 48), thereby permitting ink from the pressurized ink source (46, 48) to flow through the channel (61, 62, 64, 66) and thereafter be ejected from the nozzle (42) when the pressurized ink source (46, 48) has attained a particular threshold pressure.

Abstract: A printer selectively ejects ink droplets or jets out ink mists depending upon input data of an image to be recorded. The printer has a drive signal generating section and a recording head. The drive signal generating section generates two drive signals, first one for causing the recording head to eject ink droplets to record edge portions of a solid tone level of gradation in the image and the second one for causing the recording head to jet out ink mists to record portions in the image other than the edge portions. The first signal has lower frequency than the second signal. The recording head has liquid ink chambers, each of which has an ink nozzle. A liquid level of ink in each liquid ink chamber is controlled when the first signal or the second signal is applied to the recording head.

Abstract: A droplet generator for a continuous stream ink jet print head includes an elongate cavity for containing the ink, nozzle orifices in a wall of the cavity for passing ink from the cavity to form jets. The nozzle orifices extend along the length of the cavity. An actuator is disposed on the opposite side of the cavity to the wall for vibrating the ink in the cavity by itself vibrating relative to the wall. The vibration is such that each jet breaks up into ink droplets at the same predetermined distance from the wall of the cavity. The thickness of the wall through which the nozzle orifices extend is less than 90 &mgr;m. The wall includes a planar member secured to the remainder of the droplet generator so as to form a boundary which extends around the nozzle orifices and within which the planar member is unsupported. The boundary includes first and second boundary lengths which extend along the length of the cavity on either side of the nozzle orifices.

Abstract: A system and method are provided for improving the reliability for operation of the eyelid associated with the ink jet printhead of a continuous ink jet printer. The eyelid actuation technique of the present invention solves the problem of ink jet fluid residue drying in or around the seal region between the eyelid and the catcher. This is accomplished by opening the eyelid at least once during the shutdown sequence of the printhead, while maintaining vacuum on the catcher throat. By opening the eyelid in this manner, the capillary forces that had held the ink jet fluid at the seal region are eliminated. The vacuum on the catcher throat then causes air to rush in through the gap between the catcher pan and the eyelid. Residual ink jet fluid at the seal region on both the eyelid and the catcher pan is then removed by the high velocity air moving through the gap.

Abstract: Using an electrostatic mechanism for inkjet printers to improve image quality is disclosed. A carriage assembly for such a printer includes one or more inkjet print heads, and an electrostatic mechanism. Each inkjet print head ejects ink from a corresponding ink supply in droplets as needed and aimed on a media. The droplets each have either an improper drop size or a proper drop size. The proper drop size is greater than a first threshold, whereas the improper drop size is less than a second threshold that is itself less than the first threshold. The electrostatic mechanism prevents droplets of the improper drop size from reaching the media. The mechanism has an electrostatic charge sufficiently great to affect the droplets having the improper drop size, without substantially affecting the droplets having the proper drop size.

Abstract: An apparatus for printing an image is provided. The apparatus includes a droplet forming mechanism operable in a first state to form droplets having a first volume travelling along a path and in a second state to form droplets having a plurality of other volumes travelling along the same path. A droplet deflector system applies force to the droplets travelling along the path. The force is applied in a direction such that the droplets having the first volume diverge from the path while the droplets having the plurality of other volumes remain travelling substantially along the path or diverge slightly and begin travelling along a gutter path.